% GGH Cryptosystem, challenges in dimension n: 
% 
% This file contains a public basis B and a corresponding ciphertext c
% 
% B is given in a row-order matrix format as follows 
%       B = [ 
%       ( b11 b12 ... b1n )
%       ( b21 b22 ... b2n )
%       ...
%       ( bn1 bn2 ... bnn )
%       ]
% The COLUMNS of the B matrix are the basis vectors of the lattice. 
% Namely, The lattice defined by B is L(B) = { Bx : x is an integer vector }
% 
% These public basis was generated by first picking a matrix 
%       R = (4*round(sqrt(n)+1)*I + RAND
% where I is the identity matrix and RAND is an integer matrix whose 
% entries are chosen from the range { -4, ..., +3 }, and then mixing 
% the matrix R to get a larger basis for the same lattice. 
% 
% 
% The ciphertext was computed from the public key as 
%       c = Bx + e, 
% where x is an integer vector whose entries are chosen from the range 
% {-128, ..., +127}, and e is an integer vector whose entries are chosen 
% from the set {-3,+3}. 
%
% The ciphertext is given in a vector format as follows 
%       c = [ c1 c2 ... cn ]
% (Note, however, that we think of c as a column vector.)
%